The Sevilleta de la Joya Grant was eventually sold to General Thomas Campbel by Socorro County in 1936. The Campbell family worked the land and operated a cattle ranch on it for more than 30 years. Recognizing the need for change, Campbell organized the Cambell Family Foundation in 1966, before his death. After careful consideration, the Foundation determined that the best way to preserve and enhance the integrity and the natural character of the ecosystems contained within the property would be through the creation of a national wildlife refuge. They wanted the land to be maintained in its natural state and the natural ecological successions and processes typical of the area to prevail. It was also the wish of the Foundation that portions of the property be made available to educational institutions and conservation organizations for scientific research, study and other compatible activities. In 1973 the Campbell Family Foundation donated the property to The Nature Conservancy (TNC). TNC, in turn, donated it to the US Fish and Wildlife Service (USFWS). On December 28, 1973 the Sevilleta NWR was established, thus concluding another chapter in the La Joya Land Grant History.